Abstract

Aims: The purpose of this study was to investigate a possible role of serum LDH as a predictor of cancer cell activity and to determine if serum LDH levels can prognosticate the duration of pain-free period after radionuclide therapy. Methods: The We selected 62 breast cancer patients with ages ranging from 29-67 years (mean age 53.2 ± 9.5 years) who had a successful response to radionuclide therapy with 153Sm-oxabifore and had their serum LDH levels determined prior to the therapy. Patients with a history of a benign disease, which could possibly influence the serum LDH levels, or those suffering from complications such as a vertebral fracture or impending cord compression, were excluded from the study. 153Sm-oxabifore was administrated in a standard dose of 37 MBq per kg body weight. All patients were on bisphosphonate therapy, both before and after samarium-153 treatment. Group 1 comprised of 23 patients who had received combined 153Sm-oxabifore and zoledronic acid therapy. Group 2 comprised of 39 patients who had additionally received therapy for their primary tumour. For each of these two groups, the correlation between serum LDH levels and duration of the pain-free syndrome was estimated. Results: There was a strong negative correlation (r = -0.84) between the serum LDH levels and the duration of pain-free period in Group 1, but no significant correlation (r = 0.1) was seen between the LDH levels and the duration of pain-free period in Group 2. The duration of pain-free period in the second group was longer in comparison to the first group and was statistically significant (p < 0.0001). Conclusion: Serum LDH level can prognosticate the duration of the pain-free period after radionuclide therapy and could be useful in selecting patients who in addition to samarium-153 therapy may additionally benefit from treatment of the primary tumour.